DATABASE SCOPE
A "various artist compilation" is defined as containing songs by at least three or more bands.
Stylistically the database concentrates on rock'n'roll from the mid-late 60s. In general pre-British Invasion bands aren't included, and progressive rock collections are omitted as well. The focus is primarily on bands or songs that failed to make the charts, so compilations of hit songs are excluded, even if they mainly include so-called "one-hit-wonder" garage bands like the Standells and Shadows of Knight. The database admittedly has a bias towards the U.S. and British charts when it comes to deciding what a "hit" is, so collections of songs that were huge in Australia or Holland but unheard elsewhere are included.
Where only some of a comp's songs meet the criteria for inclusion the database will often only contain these songs rather than the entire track list. This is indicated by the "More Tracks on Comp than Shown" check box on the Search by Compilation Title screen.
There are many exceptions to the rules listed above. I haven't heard all the comps included, and in these cases (mainly original 60s releases) have erred on the side of caution and provided the entire track lists, resulting in the likely inclusion of artists or songs that in no way can be described as "garage," "psychedelic" or even "rock'n'roll." Major label collections focusing on smaller countries such as Greece and Holland can have a high percentage of dross as well. Because there was often a very fine line between surf and garage, or psych and prog, a number of surf and progressive bands can be found in the database.
I'm no longer making a serious effort to include cassette comps unless they were legitimately issued or are the only format in which the songs can be found (often the case for modern bands). I'm also no longer including CD-Rs (though the few added to this point will remain).